package com.ssish.common.insurance.utils;

import java.lang.reflect.Method;
import java.util.Collection;
import java.util.Map;
import java.util.Set;


public final class JsonUtil
{

	/**
	 * 把对象封装为JSON格式
	 * 
	 * @param o
	 *            对象
	 * @return JSON格式
	 */
	@SuppressWarnings("unchecked")
	public static String toJson(final Object o)
	{
		if (o == null)
		{
			return "null";
		}
		if (o instanceof String) //String
		{
			return string2Json((String) o);
		}
		if (o instanceof Boolean) //Boolean
		{
			return boolean2Json((Boolean) o);
		}
		if (o instanceof Number) //Number
		{
			return number2Json((Number) o);
		}
		if (o instanceof Map) //Map
		{
			return map2Json((Map<String, Object>) o);
		}
		if (o instanceof Collection) //List  Set
		{
			return collection2Json((Collection) o);
		}
		if (o instanceof Object[]) //对象数组
		{
			return array2Json((Object[]) o);
		}

		if (o instanceof int[])//基本类型数组
		{
			return intArray2Json((int[]) o);
		}
		if (o instanceof boolean[])//基本类型数组
		{
			return booleanArray2Json((boolean[]) o);
		}
		if (o instanceof long[])//基本类型数组
		{
			return longArray2Json((long[]) o);
		}
		if (o instanceof float[])//基本类型数组
		{
			return floatArray2Json((float[]) o);
		}
		if (o instanceof double[])//基本类型数组
		{
			return doubleArray2Json((double[]) o);
		}
		if (o instanceof short[])//基本类型数组
		{
			return shortArray2Json((short[]) o);
		}
		if (o instanceof byte[])//基本类型数组
		{
			return byteArray2Json((byte[]) o);
		}
		if (o instanceof Object) //保底收尾对象
		{
			return object2Json(o);
		}

		throw new RuntimeException("不支持的类型: " + o.getClass().getName());
	}

	/**
	 * 将 String 对象编码为 JSON格式，只需处理好特殊字符
	 * 
	 * @param s
	 *            String 对象
	 * @return JSON格式
	 */
	static String string2Json(final String s)
	{
		final StringBuilder sb = new StringBuilder(s.length() + 20);
		sb.append('\"');
		for (int i = 0; i < s.length(); i++)
		{
			final char c = s.charAt(i);
			switch (c)
			{
			case '\"':
				sb.append("\\\"");
				break;
			case '\\':
				sb.append("\\\\");
				break;
			case '/':
				sb.append("\\/");
				break;
			case '\b':
				sb.append("\\b");
				break;
			case '\f':
				sb.append("\\f");
				break;
			case '\n':
				sb.append("\\n");
				break;
			case '\r':
				sb.append("\\r");
				break;
			case '\t':
				sb.append("\\t");
				break;
			default:
				sb.append(c);
			}
		}
		sb.append('\"');
		return sb.toString();
	}

	/**
	 * 将 Number 表示为 JSON格式
	 * 
	 * @param number
	 *            Number
	 * @return JSON格式
	 */
	static String number2Json(final Number number)
	{
		return number.toString();
	}

	/**
	 * 将 Boolean 表示为 JSON格式
	 * 
	 * @param bool
	 *            Boolean
	 * @return JSON格式
	 */
	static String boolean2Json(final Boolean bool)
	{
		return bool.toString();
	}

	/**
	 * 将 Collection 编码为 JSON 格式 (List,Set)
	 * 
	 * @param c
	 * @return
	 */
	static String collection2Json(final Collection<Object> c)
	{
		final Object[] arrObj = c.toArray();
		return toJson(arrObj);
	}

	/**
	 * 将 Map<String, Object> 编码为 JSON 格式
	 * 
	 * @param map
	 * @return
	 */
	static String map2Json(final Map<String, Object> map)
	{
		if (map.isEmpty())
		{
			return "{}";
		}
		final StringBuilder sb = new StringBuilder(map.size() << 4); //4次方
		sb.append('{');
		final Set<String> keys = map.keySet();
		for (final String key : keys)
		{
			final Object value = map.get(key);
			sb.append('\"');
			sb.append(key); //不能包含特殊字符
			sb.append('\"');
			sb.append(':');
			sb.append(toJson(value)); //循环引用的对象会引发无限递归
			sb.append(',');
		}
		// 将最后的 ',' 变为 '}': 
		sb.setCharAt(sb.length() - 1, '}');
		return sb.toString();
	}

	/**
	 * 将数组编码为 JSON 格式
	 * 
	 * @param array
	 *            数组
	 * @return JSON 格式
	 */
	static String array2Json(final Object[] array)
	{
		if (array.length == 0)
		{
			return "[]";
		}
		final StringBuilder sb = new StringBuilder(array.length << 4); //4次方
		sb.append('[');
		for (final Object o : array)
		{
			sb.append(toJson(o));
			sb.append(',');
		}
		// 将最后添加的 ',' 变为 ']': 
		sb.setCharAt(sb.length() - 1, ']');
		return sb.toString();
	}

	static String intArray2Json(final int[] array)
	{
		if (array.length == 0)
		{
			return "[]";
		}
		final StringBuilder sb = new StringBuilder(array.length << 4);
		sb.append('[');
		for (final int o : array)
		{
			sb.append(Integer.toString(o));
			sb.append(',');
		}
		// set last ',' to ']':
		sb.setCharAt(sb.length() - 1, ']');
		return sb.toString();
	}

	static String longArray2Json(final long[] array)
	{
		if (array.length == 0)
		{
			return "[]";
		}
		final StringBuilder sb = new StringBuilder(array.length << 4);
		sb.append('[');
		for (final long o : array)
		{
			sb.append(Long.toString(o));
			sb.append(',');
		}
		// set last ',' to ']':
		sb.setCharAt(sb.length() - 1, ']');
		return sb.toString();
	}

	static String booleanArray2Json(final boolean[] array)
	{
		if (array.length == 0)
		{
			return "[]";
		}
		final StringBuilder sb = new StringBuilder(array.length << 4);
		sb.append('[');
		for (final boolean o : array)
		{
			sb.append(Boolean.toString(o));
			sb.append(',');
		}
		// set last ',' to ']':
		sb.setCharAt(sb.length() - 1, ']');
		return sb.toString();
	}

	static String floatArray2Json(final float[] array)
	{
		if (array.length == 0)
		{
			return "[]";
		}
		final StringBuilder sb = new StringBuilder(array.length << 4);
		sb.append('[');
		for (final float o : array)
		{
			sb.append(Float.toString(o));
			sb.append(',');
		}
		// set last ',' to ']':
		sb.setCharAt(sb.length() - 1, ']');
		return sb.toString();
	}

	static String doubleArray2Json(final double[] array)
	{
		if (array.length == 0)
		{
			return "[]";
		}
		final StringBuilder sb = new StringBuilder(array.length << 4);
		sb.append('[');
		for (final double o : array)
		{
			sb.append(Double.toString(o));
			sb.append(',');
		}
		// set last ',' to ']':
		sb.setCharAt(sb.length() - 1, ']');
		return sb.toString();
	}

	static String shortArray2Json(final short[] array)
	{
		if (array.length == 0)
		{
			return "[]";
		}
		final StringBuilder sb = new StringBuilder(array.length << 4);
		sb.append('[');
		for (final short o : array)
		{
			sb.append(Short.toString(o));
			sb.append(',');
		}
		// set last ',' to ']':
		sb.setCharAt(sb.length() - 1, ']');
		return sb.toString();
	}

	static String byteArray2Json(final byte[] array)
	{
		if (array.length == 0)
		{
			return "[]";
		}
		final StringBuilder sb = new StringBuilder(array.length << 4);
		sb.append('[');
		for (final byte o : array)
		{
			sb.append(Byte.toString(o));
			sb.append(',');
		}
		// set last ',' to ']':
		sb.setCharAt(sb.length() - 1, ']');
		return sb.toString();
	}

	public static String object2Json(final Object bean)
	{
		//数据检查
		if (bean == null)
		{
			return "{}";
		}
		final Method[] methods = bean.getClass().getMethods(); //方法数组
		final StringBuilder sb = new StringBuilder(methods.length << 4); //4次方
		sb.append('{');

		for (final Method method : methods)
		{
			try
			{
				final String name = method.getName();
				String key = "";
				if (name.startsWith("get"))
				{
					key = name.substring(3);

					//防死循环
					final String[] arrs =
					{ "Class" };
					boolean bl = false;
					for (final String s : arrs)
					{
						if (s.equals(key))
						{
							bl = true;
							continue;
						}
					}
					if (bl)
					{
						continue; //防死循环
					}
				}
				else if (name.startsWith("is"))
				{
					key = name.substring(2);
				}
				if (key.length() > 0 && Character.isUpperCase(key.charAt(0)) && method.getParameterTypes().length == 0)
				{
					if (key.length() == 1)
					{
						key = key.toLowerCase();
					}
					else if (!Character.isUpperCase(key.charAt(1)))
					{
						key = key.substring(0, 1).toLowerCase() + key.substring(1);
					}
					final Object elementObj = method.invoke(bean);

					//System.out.println("###" + key + ":" + elementObj.toString());

					sb.append('\"');
					sb.append(key); //不能包含特殊字符
					sb.append('\"');
					sb.append(':');
					sb.append(toJson(elementObj)); //循环引用的对象会引发无限递归
					sb.append(',');
				}
			}
			catch (final Exception e)
			{
				//e.getMessage();
				throw new RuntimeException("在将bean封装成JSON格式时异常：" + e.getMessage(), e);
			}
		}
		if (sb.length() == 1)
		{
			return bean.toString();
		}
		else
		{
			sb.setCharAt(sb.length() - 1, '}');
			return sb.toString();
		}
	}

	private JsonUtil()
	{
	}
}
